Numerous approaches have been made with various constructions for arm exercising and strength testing devices such as those disclosed in the following U.S. patents: 1,189,396 Sheridan 3,428,311 Mitchell 3,467,376 Feinberg 3,563,542 Wellman et al 3,633,907 Cane et al 3,662,602 Weiss 3,713,653 Romans 3,815,904 Weiss et al
Some of these employ an elongated rigid member; others employ a plurality of springs interconnecting a reference plate to a handle. However, all of such prior art constructions are relatively complicated and none to the best of applicant's knowledge employs an adjustable helical spring and sleeve mounting wherein the arm force is directly absorbed by bending a simple coiled spring.